Legend:

I think there is an issue here: https://www.openstreetmap.org/way/237778620 this object is flagged with a warning. However, auto-fixing this object moves the nodes by less than the JOSM object history window can display as coordinates (7 decimal places) and it displays "< 0.01 m" difference. Such very very very minor non-square buildings should not be flagged (creates more noise than benefit). I would not like to see edits for such square buildings. Would that non-change be saved in the OSM database as anything but a useless changeset (coordinates are only 7 decimal places in the API)?